path: root/qemu-img.texi
diff options
authorStefan Hajnoczi <stefanha@linux.vnet.ibm.com>2012-06-13 14:29:15 +0100
committerKevin Wolf <kwolf@redhat.com>2012-06-15 14:03:43 +0200
commitf085800e245836fed27fddb3b624a29326637657 (patch)
treeee89e965575bb7e34b85be32c84cec68b4e556d8 /qemu-img.texi
parent0446919dcab51e7468f346c0a009a88632c5c5e0 (diff)
qemu-img: document qed format on qemu-img man page
The qemu-img.1 man page is missing the qed format from its list of supported formats. Document the image creation options for qed. Suggested-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qemu-img.texi')
1 files changed, 23 insertions, 0 deletions
diff --git a/qemu-img.texi b/qemu-img.texi
index 5a7b2bb1f2..77c6d0b6b0 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -237,6 +237,29 @@ to grow.
@end table
+@item qed
+Image format with support for backing files and compact image files (when your
+filesystem or transport medium does not support holes). Good performance due
+to less metadata than the more featureful qcow2 format, especially with
+cache=writethrough or cache=directsync. Consider using qcow2 which will soon
+have a similar optimization and is most actively developed.
+Supported options:
+@table @code
+@item backing_file
+File name of a base image (see @option{create} subcommand).
+@item backing_fmt
+Image file format of backing file (optional). Useful if the format cannot be
+autodetected because it has no header, like some vhd/vpc files.
+@item cluster_size
+Changes the cluster size (must be power-of-2 between 4K and 64K). Smaller
+cluster sizes can improve the image file size whereas larger cluster sizes
+generally provide better performance.
+@item table_size
+Changes the number of clusters per L1/L2 table (must be power-of-2 between 1
+and 16). There is normally no need to change this value but this option can be
+used for performance benchmarking.
+@end table
@item qcow
Old QEMU image format. Left for compatibility.